A mesopore molecular sieve is a new material which is expected, as an inorganic porous substance having a uniform pore size in a mesopore region, to be used in wide applications such as catalysts and adsorbents. U.S. Pat. Nos. 5,098,684, 5,102,643 and 5,108,725 and JP-W-A-5-503499 (the term "JP-W-A" as used herein means a "published Japanese national stage of international application") disclose a process for synthesizing a mesopore molecular sieve by using, as a template, a quaternary ammonium salt or phosphonium salt having a long-chain alkyl group and conducting hydrothermal synthesis.
JP-A-4-238810 (the term "JP-A" as used herein means an "unexamined published Japanese patent application") discloses a process for synthesizing a mesopore molecular sieve by treating a layered silica with a long-chain alkyl ammonium cation in accordance with an ion exchange method.
JP-A 5-254827 discloses a process for modifying a synthesized mesopore molecular sieve, which comprises treating the sieve with an alkylsilane coupling agent having a methyl group, etc. reactions with a silanol group etc. which exists on the surface of the mesopore skeleton, thereby adding an alkylailyl group to control the pore size or adding a trimethylailyl group to modify the surface.
An object of the present invention is to provide a novel mesopore molecular sieve which has a hydrocarbon group bonded directly to a silicon atom constituting the skeleton of the molecular sieve and a production process thereof.